class_docstr: Policy object that implements actor critic, using a MLP (2 layers of 64), with layer normalisation
  
  :param sess: (TensorFlow session) The current TensorFlow session
  :param ob_space: (Gym Space) The observation space of the environment
  :param ac_space: (Gym Space) The action space of the environment
  :param n_env: (int) The number of environments to run
  :param n_steps: (int) The number of steps to run for each environment
  :param n_batch: (int) The number of batch to run (n_envs * n_steps)
  :param reuse: (bool) If the policy is reusable or not
  :param _kwargs: (dict) Extra keyword arguments for the nature CNN feature extraction
code: def __init__(
      self,
      sess,
      ob_space,
      ac_space,
      n_env=1,
      n_steps=1,
      n_batch=None,
      reuse=False,
      **_kwargs,
  ):
      super(LnMlpPolicy, self).__init__(
          sess,
          ob_space,
          ac_space,
          n_env,
          n_steps,
          n_batch,
          reuse,
          feature_extraction="mlp",
          layer_norm=True,
          **_kwargs,
      )
  
imports: import tensorflow
  from gym.spaces import Box
  from stable_baselines.common.policies import BasePolicy, nature_cnn, register_policy
  from stable_baselines.common.tf_layers import mlp
label_desc: Use image node_id 1 to create a new LnMlpPolicy object from inherited base classes: FeedForwardPolicy with example: obj = LnMlpPolicy(sess, ob_space, ac_space, n_env, n_steps, n_batch, reuse)